Peter Houston Kostmayer (born September 27, 1946) is a Democratic politician who served seven terms in the U.S. House of Representatives from Bucks County, Pennsylvania.

Kostmayer was born in New York City, graduated from West Nottingham Academy in Colora, Maryland, in 1965, and received a B.A.

Following the retirement of U.S. Rep. Edward Biester in 1976, Kostmayer ran against State Representative John S. Renninger for the open seat in Pennsylvania's 8th congressional district.

[5] He then enjoyed victories in 1986 over David Christian again by a much larger margin and in 1988 over PA Republican State Senator Edward Howard and then again in 1990 over Bucks County Clerk of Courts, Audrey Zettick.

[7] Kostmayer is the retired CEO of the Citizens Committee for New York City and lives in Clinton Hill, Brooklyn.